From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 61D88E909D4 for ; Tue, 17 Feb 2026 16:57:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Type:MIME-Version:References:Message-ID:Subject:To:From:Date:Reply-To :Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HCwMruxlpjec1xfWAL85VuiIFN2j5Ld4KHWlaGonawQ=; b=nRUUeKKj0JA8H4GUp9Rix5AhvA othFgvAyD2bCfkjySCMQ2KnI0h48QfV2bsd9KDk4Tfr6rgfegbEAHx7LIG+EvxZQY0crSVcuxlkHz wnz8SEDUVpD7itAQO+uFs2S6FBXclxNRGHVUOJMDYsF+Jvt36knqR+10HR1G+cUdOh4D63KNr3t4Q WuCuZSr/JecDcyK4bsOxr83yy7/kqwaYgeowcodJx1ZD2HwaOB645vbWeoT0kEiDyAVPO1/M8MtBB trksfqxzR9pP1onbdh4/ithK6Eh4clSTr/5XLwBvLA9oeg4/3B+67u+YdeWj2Bj7XKy8cAysP2fuo /gsmF+EA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vsOO1-00000008bdv-2ERF; Tue, 17 Feb 2026 16:57:21 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vsONt-00000008bce-47Jz for linux-arm-kernel@lists.infradead.org; Tue, 17 Feb 2026 16:57:19 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8B9C91477; Tue, 17 Feb 2026 08:57:06 -0800 (PST) Received: from J2N7QTR9R3.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3E3853F62B; Tue, 17 Feb 2026 08:57:11 -0800 (PST) Date: Tue, 17 Feb 2026 16:57:08 +0000 From: Mark Rutland To: Khaja Hussain Shaik Khaji Subject: Re: [PATCH v2 2/2] arm64: insn: drop NOP from steppable hint list Message-ID: References: <20251106104955.2089268-1-khaja.khaji@oss.qualcomm.com> <20260217133855.3142192-1-khaja.khaji@oss.qualcomm.com> <20260217133855.3142192-3-khaja.khaji@oss.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260217133855.3142192-3-khaja.khaji@oss.qualcomm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260217_085715_334048_8B62B4DB X-CRM114-Status: GOOD ( 14.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: catalin.marinas@arm.com, dev.jain@arm.com, linux-kernel@vger.kernel.org, yang@os.amperecomputing.com, linux-arm-msm@vger.kernel.org, will@kernel.org, linux-arm-kernel@lists.infradead.org, mhiramat@kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Feb 17, 2026 at 07:08:55PM +0530, Khaja Hussain Shaik Khaji wrote: > NOP is already handled via instruction emulation and does not require > single-stepping. Drop it from aarch64_insn_is_steppable_hint(). > > Signed-off-by: Khaja Hussain Shaik Khaji > --- > arch/arm64/include/asm/insn.h | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h > index e1d30ba99d01..9429f76906e0 100644 > --- a/arch/arm64/include/asm/insn.h > +++ b/arch/arm64/include/asm/insn.h > @@ -456,7 +456,6 @@ static __always_inline bool aarch64_insn_is_steppable_hint(u32 insn) > case AARCH64_INSN_HINT_BTIC: > case AARCH64_INSN_HINT_BTIJ: > case AARCH64_INSN_HINT_BTIJC: > - case AARCH64_INSN_HINT_NOP: > return true; > default: > return false; The intent is that aarch64_insn_is_steppable_hint() says whether an instruction is safe to step, not whether it *must* be stepped. I think we can leave NOP here unless this is causing some functional problem? Mark.